Circuit breaker



J. J; ZELLER CIRCUIT BREAKER July 19, 1949.

2 Sheets-Sheet 1 Filed June 4, 1945 INVENTOR. f JZeZZe/T BY @FW FTTOfi'A/EX y 9, 1949. J, J. ZELLER 2,476,648

CIRCUIT BREAKER Patented July 19, 1949 CIRCUIT BREAKER Josef J. Zeller, Detroit, Mich., assignor to Square D Company, Detroit, Mich., a corporation of Michigan Application June 4, 1945, Serial No. 587,498

This invention relates to electric circuit breakers having manual and automatic means for effecting contact separation.

One object of the invention is the provisionof an automatic electric circuit breaker in which the manual switching action and reset are effected through the reciprocation of a push button operator.

Another object of the-invention is the provision of an automatic electric circuit breaker in which the manual opening of the contacts is effected by the movement bodily of an element, normally latched by a current responsive element, into an unlatching position permitting operation of the circuit breaker mechanism to separate the contacts.

Other objects and features of the invention will be readily apparent to those skilled in the art from the specification and appended drawings illustrating certain preierred embodiments in which:

Figure 1 is a front elevational view of an automatic electric circuit breaker according to the present invention.

Figure 2 is an enlarged longitudinal sectional view through the breaker of Figure 1.

Ffi'gure 3 is a view similar to Figure 2 but showing the parts in open circuit position.

Figure 4 is an exploded perspective view of certain of theoperating parts of the circuit breaker.

The circuit breaker, according to the present invention, as specifically illustrated in the drawings, comprises a cup-shaped base member I, having a closing cover formed by insulating plates 2 and 3, and an outer metallic plate 4 maintained in sealed relation on the base I by rivets 5. The plate 4 is provided with a pair of threaded hollow rivets 8 for mounting the breaker in position.

Within the base I is mounted a supporting bracket I carrying on opposite side walls a stationary pivot pin 8 upon which is pivotally mounted a generally U-shaped conducting element 9 having its bight extended to form a contact arm II carrying movable contact I2. Also mounted on the pin 8 through a slot I3 is a trigger element I4 mounted to pivot about the pin 8 and through slot I3 to be moved bodily relative thereto. The trigger element I4 is biased by tension spring I5 for movement in a counterclockwise direction a viewed in Figure 2. The trigger element I4 is provided with a latch tip I6 adapted to be engaged by the end of a bimetallic member I! mounted upon a conducting connector I8 extending through the base I and terminating at the back thereof in the terminal connector I8.

- eoiaims. (01. 200-116) The connector I8 is mounted in position by a stud 2| and the position of the bimetallic element I1, and, hence, the calibration of the overload current at which the breaker will trip is determined by an adjusting screw 22. A second conducting connector 23 carries stationary contact 24 and is mounted within the base I by stud 25. The connector 23 extending through the rear wall of the base I terminates in the terminal connector 26.

The metallic cover plate 4 is provided with a hub 21 within which is disposed a push button operator 28 for rectilinear movement into and out of the breaker interior. The interior end of push button operator 28 is provided with a slot 28 receiving a pin 3| carried within the opposite arms of the trigger element I4. A spring 32 disposed between the trigger element I4 and the conducting element 8 biases them for rotation in opposite directions relative to each other and, hence, serves to maintain the contact pressure between contacts I2 and 24. The conducting element 8 is provided with a leg extension 33 positioned to engage the face of latch tip I6 and also to restrict the follow-up movement of the bimetal I! on manual operation. The trigger element I4 is provided with arm extension 34 limiting its movement in a counterclockwise direction. A flexible lead 35 interconnects the switching arm I I and the end of the bimetallic element I! to establish a current path from ter minal I9, connector I8, bimetallic element Il, flexible lead 35, switching arm II, contact I2, contact 24, and connector 23 to terminal 26.

As shown in Figure 2, the circuit breaker parts are in the contacts engaged position. Upon the occurrence of a current overload, the bimetal I! will become heated and flex to the right out of engagement with the latch tip I6 on trigger element I4. Under the influence of the tension spring I5, trigger element I4 will then rotate in a counterclockwise direction and by engagement with arm 33 will carry with it the conducting element 8 to place the parts in the contacts separated position of Figure 3.

To reset the breaker into engaged position, the operator 28 is pushed inwardly to rotate the element I4 in a clockwise direction about pin 8 into the position of Figure 2 where it will again be latched by the blmetal element I1, and this movement of the element I4 will, through spring 32, also rotate the conducting element Sin a counterclockwise direction into the contacts engaged position. In this resetting movement the contacts I2 and 24 engage before the latch tip I6 is button operator 28 is pulled outwardly. As the operator 28.moves outwardly, the trigger element is will be moved bodily to the left as viewed in Figure 2, such movement being permitted by the slot it which moves relative to the pin 8. The

element it moves to the left until the latching tip it is disengaged from the bimetallic member ii whereupon the elements is and 9 will be rotated in a counterclockwise direction under the bias of spring l into the open circuit position of Figure otally mounted switching member carrying said movable contact and adapted to efiect engagement and disengagement thereof with said stationary contact, an operating member, a pivotal mounting for said operating member permitting movement thereof bodily relative to its pivotal axis, means biasing said operating mem her for rotation about its pivotal mounting to effect rotation of said switching member to contacts' disengaged position, current responsive means normally latching said'operating member in inoperative position and releasing the same for rotation under its biasing means upon the cc- 3. In this manual unlatching by movement of the trigger element it, the arm 83 prevents bimetal H from following up movement of the latching tip it. As the manual and automatic open circuit positions are the same, the resetting oi the breaker after a manual operation is identical with that previously described after an automatic opening.

While certain preferred embodiments of the invention have been specifically disclosed, it is understood that the invention is not limited thereto, as many variations will be readily apparent to those skilled in the art and the invention is to be given its broadest possible interoperative position, means biasing said operating member to move said switching member to contacts disengaged positionupon release oi said operating member by said current responsive means upon the occurrence of a current overload through the circuit breaker, and manual means for bodily moving said" operating member out of engagement with said current responsive latching currence of a current overload through the circuit breaker, manual means for bodily moving said operating member into an unlatohed position to eflect its rotation under the action of said biasing means at will, said manual means efiecting return of said switching member to contacts engaged position and of said operating member to relatched position after either manual or automatic release of said operating member.

4. In an automatic electric circuit breaker, a stationary contact, a movable contact, a pivotally mounted switching member carrying said movable contact and adapted to effect engagement and disengagement thereof with said stationary contact, an operating member, a pivotal mountmeans for movement of said operating member member to its unlatohed position, and means for and switching member under said biasing means to contacts disengaged position at will, said manual means also eflectlng relatching of said operating member and reengagement of said contacts after either manual or automatic release of the operating member.

2. In an automatic electric circuit breaker, a stationary contact, a movable contact, a switching member carrying said movable contact, an operating member, current responsive means normally latching said operating member in inoperative position, means biasing said operating member to move said switching member to contacts disengaged position upon release of said operating member by said current responsive means upon the occurrence of a current overload through the circuit breaker, manual means for member by rectilinear movement of said push button operator in the opposite direction.

3. In an automatic electric circuit breaker, a stationary contact, a movable contact, a piving for said operating member permitting movement thereof bodily relative to its pivotal axis, means biasing said operating member for rotation about its pivotal mounting to eflect rotation of said switching member to contacts disengaged position, current responsive means normally latching said operating member in inoperative position and releasing the same for rotation under'its, biasing means upon the occurrence of a current overload through the circuit breaker, manual means for bodily moving said operating member into an unlatohed position to effect its rotation under the action of said biasing means at will, said manual means including a reciprocable push button operator which is pulled to \eflect the movement bodily of the Operating eflecting reset of said switching member and operating member upon a pushing movement of said push button operator.

5. In an automatic electric circuit breaker, a stationary contact, a movable contact, a. pivotally mounted switching member carrying said movable contact intoand out of engagement with said stationary contact,'an operating member having a pin and slot pivotal mounting, means biasing said operating member for rotation about its pivotal mounting, current responsive means normally latching said operating member in inoperative position, means interconnecting said operating member and switching member to effect movement 01 said switching member upon rotation of said operating member, a reciprocable push button operator, means providing a pin and slot connection between said push button operator and said operating member whereby movement of said push button operator in I one direction eflects movements bodily of said operating member out of engagement with said current responsive latching means by relative movement of said first mentioned pin and slot mounting 'to eii'ect rotation of the operating member about its pivotal mounting and movement of said switching member to contacts disengaged position.

6. In an automatic electric circuit breaker, a stationary contact, a movable contact, a pivotally mounted switching member carrying said movable contact into and out of engagement with said stationary contact, an operating member having a pin and slot pivotal mounting, means biasing said operating member for rotation about its pivotal mounting, current responsive means normally latching said operating member in inoperative position, means interconnecting said operating member and switching member to effect movement of said switching member upon rotation of said operating member, a reciprocable push button operator, means interconnecting said push button operator and said operating member whereby movement of said push button operator in one direction effects movement bodily of said operating member out of engagement with said current responsive latching means by relative movement of said pin and slot mounting to eifect rotation of the operating member about its pivotal mounting and movement of said switching member to contacts disengaged position, movement of said push button operator in the reverse direction effecting reset or said switching member and operating member, said interconnecting means between said switching member and said operating member including a spring stressed in the reset position to efiect contact pressure between the engaged contacts.

JOSEF J. ZELLER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

